Easy opening end



April25,1967 A. R; BOIK ETAL 3,315,837

EASY OPENING END Filed Nov. 25, 1964 INVENTORS ARNOLD R. BOIK F EDERICK J. STEC ATTORNEYS United States Patent 3,315,837 EASY OPENING END Arnold R. Boik, Chicago, and Frederick J. Stec, Oak Lawn, 11]., assignors to Continental Can Company, Inc., New York, N.Y., a corporation of New York Filed Nov. 25, 1964, Ser. No. 413,933 12 Claims. (Cl. 220-54) This invention relates in general to new and useful improvements in easy opening cans, and more particularly to a can end particularly adapted to be utilized as part of a can for containing beverages packed under pressure.

Many liquids, particularly beverages, are packed in cans under gaseous pressure. Also, in many instances the gas utilized in packaging the beverage under pressure is one which may be released upon agitation with the result that if a can is dropped or shaken immediately before open ing, there is a much greater than normal pressure within the can. It has been found that with the present type easy opening cans When an undue gaseous pressure exists within the can and the can is opened by initiating the tearing off of the removable tear strip of the can, the pressure within the can reacts on the tear strip and causes a blow-out which results in the uncontrolled tearing of the tear strip from the can end.

It is the primary object of this invention to prevent blow-outs of the type set forth above without materially changing existing easy opening can end constructions. In accordance with this invention, it is proposed to locally increase the resistance to tearing of the can end along the score lines defining the removable tear strip at points immediately adjacent the connection of a pull tab to the tear strip. This is accomplished by re-forming the end panel of the can end adjacent the score lines so as to decrease the width of the score lines without materially varying the depths thereof.

It is proposed to form an easy opening can end in the normal manner, and after the tear strip has been outlined by the forming of score lines in the end panel, to displace the metal of the tear strip transversely outwardly of the tear strip into the spaces defined by the score lines so that the flow of the metal results in the reduction in the width of each score line and the resultant increase in resistance of the end panel to tearing.

A further object of this invention is to provide a novel can end of the easy opening type which includes a removable tear strip defined by score lines and wherein the tear strip has attached thereto a pull tab for eflecting the rupture of the end panel and the tearing of the tear strip therefrom, the tear strip having a central portion thereof adjacent the connection thereof with the pull tab outwardly displaced to define a longitudinally extending groove with the material displaced from the tear strip central portion being flowed into the spaces of the score lines so as to reduce the cross sections of the score lines whereby the resistance of the end panel to tearing is increased and at the same time the resistance of the tear strip to transverse folding is decreased. 1

With the above and other objects in view that will hereinafter appear, the nature of the invention will be more clearly understood by reference to the following detailed description, the appended claims and the several views illustrated in the accompanying drawing.

In the drawing:

FIGURE 1 is a fragmentary top perspective view of a can formed in accordance with this invention.

FIGURE 2 is an enlarged fragmentary plan view of the can of FIGURE 1 and shows the specific easy opening details of the can end closing the upper end thereof.

FIGURE 3 is an enlarged fragmentary plan view of that portion of the can end which has been worked upon in accordance with this invention and shows the specific details thereof.

FIGURE 4 is an enlarged fragmentary vertical sectional view taken transversely of the tear strip through the can end only and shows the specific details of the cross section of the can end through the tear strip area.

FIGURE 5 is an enlarged fragmentary vertical sectional view taken through the upper part of the can of FIGURE 1 and shows the manner in which the starting end portion of the tear strip folds after the initial tearing thereof from the end panel occurs and the tearing reaches the affected area.

Referring now to the drawing in detail, it will be seen that there is illustrated a can formed in accordance with this invention, the can being generally referred to by the numeral 10. The can 10 includes a can body 11 of a conventional construction which has the lower end thereof closed in the normal manner either by an integral end or an end separately secured thereto, neither of the ends being illustrated.

The upper end of the can body 11 is closed by means of an easy opening end, generally referred to be the numeral 12, the can end 12 being secured to the can body 11 by means of a conventional double seam 13. The can end 12 includes an end panel 14 in which there are formed score lines 15 and 16 which are separately referred to, but which may be continuous. The score lines 15 and 16 define a tear strip 17 which is removable in the opening of the can 10. The tear strip 17, as is clearly shown in FIGURE 5, has a starting end portion 18 which is provided with an integral rivet 19 by means of which a pull tab 20 is secured to the tear strip 17.

The above described features of the can end 12 are well known and are used at the present time in the packaging of beverages, particularly beer, which are packed under a gaseous pressure. Such a beverage is shown in FIGURE 5 and is referred to by the numeral 21. When a can of the type described hereinabove is opened, a relatively great force is applied to the free end of the pull tab 20 to elfect the initial rupture of the end panel 14 along the score lines 15 and 16. As the end panel 14 ruptures along the starting end of the tear strip 17, the resistance to rupture of the end panel about the starting end portion of the tear strip 17 clearly reduces with the result that there is an immediate upward movement of the starting end portion 18 of the tear strip 17 before the force applied to the pull tab 20 can be reduced. Furthermore, in view of the fact that the beverage 21 is packed within the can 10 under a gaseous pressure, there is a high pressure exerted on the underside of the tear strip 17. This pressure, coupled with the force applied to the pull tab 20, causes a sudden tearing of the tear strip 17 from the end panel 14. In certain instances where the contents of the can 10 have been agitated immediately prior to the opening thereof, the force exerted by the gases Within the can 10 are sufficient to etfect a complete tearing out of the tear strip 17 and a blow off thereof in a manner which is very undesirable. This invention proposes to modify the existing type of easy opening can end to avoid this uncontrolled tearing of the tear strip from the can end.

In accordance with this invention, that portion of the tear strip 17 which is disposed adjacent the rivet 19 is worked upon to define a longitudinally extending recess 24, as is clearly shown in FIGURES 3 and 4. A suitable punch is utilized to form the recess 24. Since the recess 24 requires a displacement of the metal of the tear strip 17, and since the recess 24 extends longitudinally of the tear strip 17, it will be readily apparent that a major portion of the flow of the displaced metal will be transversely of the tear strip 17 into the spaces resulting from the formation of the score lines 15 and 16. The flowed metal is clearly shown in FIGURE 4 and is referred to by the numeral 25. It is to be noted that while the depth of the score lines 15 and 16 is not changed, the width of each score line 15 and 16 is materially decreased, thereby greatly reducing the cross section of the score lines 15 and 16 adjacent the longitudinal recess 24. This abrupt reduction in cross section of the score lines 15 and 16 provides for an abrupt resistance to the tearing of the tear strip 17 from the end panel 14. In this manner, the chances of an accidental uncontrolled tearing of the tear strip 17 from the end panel 14 are greatly reduced.

It is also pointed out at this time that when the longitudinal recess or groove 24 is formed in the tear strip 17, although there is a displacement of the metal of the tear strip transversely outwardly into the score line areas, there is a definite reduction in the cross section of the tear strip 17, as is clearly shown in FIGURE 4. As a result, in the reduction in the cross section of the tear strip 17, the resistance to bending or hinging of the tear strip 17 is decreased at the same time the resistance to tearing of the end panel is increased. Therefore, as is clearly shown in FIGURE 5, during the opening of the can 10, when the region of the displaced metal is reached, tearing of the metal of the end panel 14 suddenly decreases and a hinging action or bending of the tear strip 17 takes place. Since the pressure exerted on the tear strip starting end portion is only momentary in that the gases within the can are immediately vented out through the opening formed during the rupture of the end panel in the tearing away of the starting end portion of the tear strip, it will be seen that the tear strip 17 may then be removed in the customary manner without any uncontrolled tearing or blow-out thereof.

It will be readily apparent that the reduction in cross section of each of the score lines and the reduction in the transverse cross section of the tear strip function independently although they are simultaneously eifected, and that each could be utilized independent of the other.

Referring now to FIGURE 2 in particular, it will be seen that the tear strip 17 has an enlarged portion 26 disposed adjacent the outer periphery of the can end 12. This portion of the tear strip 17, when removed, defines a pouring portion of an opening in the can end 12. In order to prevent one from accidentally cutting ones lips on the raw edge which results after the tear strip 17 is removed, the end panel 14 is provided with a pair of ribs 27 and 28 which extend along the outer portion of the tear strip 17. These ribs 27 also reinforce the end panel 14. It is to be noted that the ribs 27 and 28 start at points transversely aligned with the recess 24 and the flowed metal 25. Thus, there is a reinforcement of the end panel 14 adjacent the point where the resistance to the tearing of the end panel is increased and the resistance to bending of the tear strip is decreased.

Although only a preferred embodiment of the invention has been specifically illustrated and described herein, it is to be understood that minor variations may be made therein within the spirit and scope of the invention, as defined by the appended claims.

We claim:

1. A can end particularly adapted for use with products packaged under gaseous pressure, said can end comprising an end panel having score lines defining a removable tear strip, said tear strip having a starting end portion to which pull means are attached, and said end panel having the appearance of having been reshaped adjacent said pull means with portions of said score lines having the appearance of having been reformed to provide for a greater resistance to tearing of said tear strip from said end panel adjacent said starting end portion whereby uncontrolled tearing and blow-out of said tear strip from said end panel after the initial rupture of said end panel due to gaseous pressure on said tear strip is prevented.

2. The can end of claim 1 wherein said end panel is reinforced on opposite sides of said tear strip starting terminal part adjacent said means for effecting transverse bending of said tear strip end portion.

3. A can end particularly adapted for use with products packaged under gaseous pressure, said can end comprising an end panel having score lines defining a removable tear strip, said tear strip having a starting end portion to which pull means are attached, and an intermediate portion of said tear strip having the appearance of having been reshaped adjacent said pull means with portions of said score lines having the appearance of having been re-formed to provide for a greater resistance to tearing of said tear strip from said end panel adjacent said starting end portion whereby uncontrolled tearing and blow-out of said tear strip from said end panel after the initial rupture of said end panel due to gaseous pressure on said tear strip is prevented.

4. A can end particularly adapted for use with products packaged under gaseous pressure, said can end comprising an end panel having score lines defining a removable tear strip, said tear strip having a starting end portion to which pull means are attached, and an intermediate portion of said tear strip having been displaced transversely outwardly with the material of said tear strip partially filling the spaces defined by said score lines to locally increase the resistance to tear of said end panel along said score lines whereby uncontrolled tearing and blo w-out of said tear strip from said end panel after the initial rupture of said end panel due to gaseous pressure on said tear strip is prevented.

5. A can end particularly adapted for use with products packaged under gaseous pressure, said can end comprising an end panel having score lines defining a removable tear strip, said tear strip having a starting end portion to which pull means are attached, and an intermediate portion of said tear strip adjacent said pull means having a centrally located longitudinal groove with the material of said tear strip displaced in the forming of said groove having reshaped transversely adjacent portions of said score lines to locally increase the resistance to tear of said end panel along said score lines whereby uncontrolled tearing and blow-out of said tear strip from said end panel after the initial rupture of said end panel due to gaseous pressure on said tear strip is prevented.

6. A can end particularly adapted for use with products packaged under gaseous pressure, said can end comprising an end panel having score lines defining a removable tear strip, said tear strip having a starting end portion to which pull means are attached, and an intermediate portion of said tear strip adjacent said pull means having a centrally located longitudinal groove with the material of said tear strip displaced in the forming of said groove having reshaped transversely adjacent portions of said score lines to locally increase the resistance to tear of said end panel along said score lines, and the transverse section of said tear strip being locally reduced to decrease the resistance of said tear strip to bending whereby uncontrolled tearing and blow-out of said tear strip from said end panel after the initial rupture of said end panel due to gaseous pressure on said tear strip is prevented.

7. A can end particularly adapted for use with products packaged under gaseous pressure, said can end comprising an end panel having a weakening line defining a tear strip which is removable in the opening of an associated can, said tear strip including an end portion having a starting terminal part to which pull means are attached, said tear strip end portion having means adjacent said starting terminal part for effecting transverse bending of said tear strip end portion in response to tearing pressure exerted on said starting terminal part after the starting terminal part has been turn away from said end panel whereby uncontrolled tearing and blow-out of said tear strip from said end panel due to gaseous pressure thereon is prevented.

3. The can end of claim 7 wherein said means for efiecting transverse bending of said tear strip end portion are in the form of an area of weakening in said tear strip end portion.

9. The can end of claim 7 wherein said means for efiecting transverse bending of said tear strip end portion are in the form of a longitudinally extending score line in said tear strip end portion.

10. A can end particularly adapted for use with products packaged under gaseous pressure, said can end comprising an end panel having a weakening line defining a tear strip which is removable in the opening of an associated can, said tear strip including an end portion having a starting terminal part, said starting terminal part including an attaching fiastener securing a pull tab to said tear strip, said tear strip end portion having means adjacent said attaching fastener for elfecting transverse bending of said tear strip end portion in response to tearing pressure exerted on said starting terminal part after the starting terminal part has been torn away from said end panel whereby uncontrolled tearing and blow-out of said tear strip from said end panel due to gaseous pressure thereon is prevented.

11. A package comprising a can body having opposite ends thereof closed by can ends, and a liquid packaged within said can under gaseous pressure, one of said can ends being adapted to be uppermost when said package is opened and being of an easy opening type, said one can end including an end panel having score lines therein defining a tear strip removable from said end panel to form a dispensing opening, said tear strip having an end portion including a starting terminal part bearing a rivet, a pull tab secured to said tear strip by said rivet and said tear strip having a line of weakening adjacent said rivet for eifecting the transverse bending of said tear strip in response to tearing pressure exerted on said starting terminal part after the starting terminal part has been torn away from said end panel whereby uncontrolled tearing and blow-out of said tear strip from said end panel due to gaseous pressure thereon is prevented.

12. The package of claim 11 wherein said tear strip line of weakening is in the form of a recess extending longitudinally of said tear strip.

References Cited by the Examiner UNITED STATES PATENTS 3,250,426 5/1964 Fraze 220-54 THERON E. CONDON, Primary Examiner. G. T. HALL, Assistant Examiner. 

1. A CAN END PARTICULARLY ADAPTED FOR USE WITH PRODUCTS PACKAGED UNDER GASEOUS PRESSURE, SAID CAN END COMPRISING AN END PANEL HAVING SCORE LINES DEFINING A REMOVABLE TEAR STRIP, SAID TEAR STRIP HAVING A STARTING END PORTION TO WHICH PULL MEANS ARE ATTACHED, AND SAID END PANEL HAVING THE APPEARANCE OF HAVING BEEN RESHAPED ADJACENT SAID PULL MEANS WITH PORTIONS OF SAID SCORE LINES HAVING THE APPEARANCE OF HAVING BEEN RE-FORMED TO PROVIDE FOR A GREATER RESISTANCE TO TEARING OF SAID TEAR STRIP FROM SAID 